| package org.superbiz.executor; |
| |
| /** |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * <p> |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * <p> |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| import javax.annotation.Resource; |
| import javax.enterprise.concurrent.ManagedExecutorService; |
| import javax.enterprise.context.RequestScoped; |
| import java.util.concurrent.CompletableFuture; |
| import java.util.concurrent.TimeUnit; |
| import java.util.function.Supplier; |
| import java.util.logging.Logger; |
| |
| import static java.util.Objects.nonNull; |
| |
| |
| @RequestScoped |
| public class ManagedService { |
| |
| private static final Logger LOGGER = Logger.getLogger(ManagedService.class.getSimpleName()); |
| |
| @Resource |
| private ManagedExecutorService executor; |
| |
| /** |
| * Executes an operation asynchronously, in a different thread provided by the {@link ManagedExecutorService}. |
| * The computation will carry on after the return of the method. |
| * |
| * @param value The demo data. |
| * @return A {@link CompletableFuture} that will return immediately. |
| */ |
| public CompletableFuture<Integer> asyncTask(final int value) { |
| LOGGER.info("Create asyncTask"); |
| return CompletableFuture |
| .supplyAsync(longTask(value, 100, null), executor) // Execute asynchronously. |
| .thenApply(i -> i + 1); // After the return of the task, do something else with the result. |
| } |
| |
| /** |
| * Executes an operation asynchronously, in a different thread provided by the {@link ManagedExecutorService}. |
| * The computation will carry on after the return of the method. |
| * |
| * @param value The demo data. |
| * @return A {@link CompletableFuture} that will return immediately. |
| */ |
| public CompletableFuture<Integer> asyncTaskWithException(final int value) { |
| LOGGER.info("Create asyncTaskWithException"); |
| return CompletableFuture |
| .supplyAsync(longTask(value, 100, "Planned exception"), executor) // Execute asynchronously. |
| .thenApply(i -> i + 1); // After the return of the task, do something else with the result. |
| } |
| |
| /** |
| * Method to simulate an asynchronous task. Will add 1 to the value for each invocation. |
| * |
| * @param value The demo data. |
| * @param taskDurationMs How long the task will take to complete. In ms. |
| * @param errorMessage Message for the exception simulating an execution problem |
| * @return a {@link Supplier} function processing the new value |
| */ |
| private Supplier<Integer> longTask(final int value, |
| final int taskDurationMs, |
| final String errorMessage) { |
| return () -> { |
| if (nonNull(errorMessage)) { |
| LOGGER.severe("Exception will be thrown"); |
| throw new RuntimeException(errorMessage); |
| } |
| |
| try { |
| // Simulate a long processing task using TimeUnit to sleep. |
| TimeUnit.MILLISECONDS.sleep(taskDurationMs); |
| } catch (InterruptedException e) { |
| throw new RuntimeException("Problem while waiting"); |
| } |
| LOGGER.info("longTask complete"); |
| return value + 1; |
| }; |
| } |
| |
| } |